Electrical power distribution systems, as frequently utilized in industry, include a busway and a power take-off assembly. As described in U.S. Pat. No. 4,804,804, the busway system consists of a housing and a plurality of generally rectangular copper or aluminum conductor busbars disposed therein.
Each busbar includes spaced tabs that protrude through the busway housing for connection with a power take-off assembly, as described in U.S. Pat. Nos. 4,758,172 and 4,886,468. A power take-off assembly generally consists of a box-like metallic or plastic enclosure containing various electrical accessories. Spring type contact blade receiver stabs protrude from the rear wall of the power take-off assembly and engage the busbar tabs. The power take-off assembly is fastened onto the busway by means of hook fasteners whereby the receiver stabs make electrical and physical contact with the tabs of the busbars. Typically, each busbar carries a separate phase of a multi-phase power distribution system with a corresponding number of receiver stabs engaging each separate busbar.
Each stab includes jaw-like clips having spring motion in one portion and flanges in the other. The jaw-like portion of the stabs protrudes through the power take-off assembly housing to attach to the busway tabs. The receiver stab flanges are typically pressed into multiple copper bars that are bolted together for electrical connection.
The copper bars are attached to a perpendicularly situated plurality of similar copper bars, comprising a "strap", which strap is in turn attached to a corresponding phase of a circuit breaker, thereby supplying electrical power from the busbars to the circuit breaker.
State-of-the-art connections containing multiple copper or aluminum bars between the stabs and the circuit breaker are labor intensive due to the multitude of bars which must be fastened together. Such take-off connections require a large amount of space and are not generally cost efficient. Since the take-offs are not thermally efficient, additional heat sinks are often required.
One purpose of the instant invention is to provide a take-off assembly that provides connection between the stabs and the circuit breaker with improved thermal and space efficiency and at a lower cost.